@each $color,
$value in $btn-colors {
    .btn {
        @include element(#{$color}) {
            @if(type-of($value)=="color") {
                @include button-variant($value, $value);
            }
            @else if(type-of($value)=="map") {
                @include button-variant(map-get($value, normal), map-get($value, normal));
            }
        }
    }
}

@each $color,
$value in $btn-colors {
    .btn {
        @include element(#{$color}) {
            @include modifier(outline) {
                @if(type-of($value)=="color") {
                    @include button-outline-variant($value, $white);
                }
                @else if(type-of($value)=="map") {
                    @include button-outline-variant(map-get($value, normal), map-get($value, active));
                }
            }
        }
    }
}